The Insymetric Synthesis Of (S)-1-Phenylsulfonyl-2-Propanolby Biocatalite And Study Of Kinetics

Optical purity of chiral compound has significant influence on its bioactivity,preparations of all kinds of high efficiency. low toxicity, weak secondary effect chiral Pharmaceuticals with optical activity need purified enantiomers.Optically active alcohols were useful chiral building blocks of natural products and synthesis of chiral medicine.As important chiral intermediates, Optically active alcohols were widely used in the production of pesticide and liquid crystals for their vital useful value,widely interesting have been aroused.It's an important way of producing optically active alcohols by stetroselective reduction of protential chiral ketongs[1], (S)-l-Phenylsulfonyl -2- Propanol can not only exhibite anticholesteremic activity but also is an important available chiral synthon. In this thesis 1-phenylsulfonyl-2-propanone has been synthesized from sodium benzenesulfinate and bromoacetone,and reduced to (S)-l-Phenylsulfonyl -2-Propanol under the prence of baker's yeast.Its primary synthetic ways were reducted by biological enzyme c.equiand bakers yeast in water,or oxidation of sulfoxide alcohol and resolution of racematic modification by lipase[23.'].Its yield is higher by c.equi,but the import price is more expensive x enzyme was deactivated easily and its yield is low;The path of oxidation or resoluted by lipase were longer,its yield was low,too;And reduted by baker's yeast in water[4],quantity of bakers yeast and saccharose were high,reaction time was longer,it was very weasted time in final treatment,yield was low.And we have done experimation again, the result was disappointing.In this paper l-Phenylsulfonyl-2-Propanone has been reducted by baker'syeast in organic solvents. Three levels and four factors orthogonal experimental was applied to affirm the condition of this reaction, effects of water quantity. reaction tiniea and pH value on this reaction yield were carried out further.The optical reaction condition was as follows: the reaction was in the constant temperature cradle(temperature 35 , 120rpm), quantity of bakers yeast and substract were 0.04556g and0.0308g in cyclohextane, respectively;quantity of water was 0.8mL.What's more in this study we have confirmed optimum condition of the reaction, its yield reached to 94.76%,in order to determinate optical purity of our product,we have separated this mixture compound,the final yield was 86.56%,optical yield got to5 =+13.59?At the same time we have studied the kinetics of thereaction,result fits in Michaelis-Menton theory,and the optimum reaction rate was obtained Vm=0,04825mol/ L ?h,in the end Michaelis constant was confirmed,that is Km=0.001338mol/L.the experimental results indicates that bakers yeast reducts l-Phenylsulfonyl-2-Propanone in organic solvents may be carried out without any question.Because we can't buy production directerly ,and in order to get standard production for determination yield by gas chromatogram,so we reducted it by chemical way, we reducted it by NaBH4 in MeOH at room temperature,got racematic l-phenylsulfinyl-2-propanol,at the same time we have identified and confirmed the structure of the final product.